Smoking system having a liquid storage portion

ABSTRACT

A smoking system includes a capillary wick for holding liquid, at least one air inlet, at least one air outlet and a chamber between the air inlet and air outlet. The air inlet, the air outlet and the chamber are arranged so as to define an air flow route from the air inlet to the air outlet via the capillary wick so as to convey aerosol formed from the liquid to the air outlet. The smoking system further includes at least one guide for channeling the air flow in the air flow route, so as to control particle size in the aerosol. The smoking system optionally includes at least one heater for heating the liquid in at least a portion of the capillary wick to form the aerosol.

CROSS-REFERENCE TO RELATED APPLICATION

This application corresponds to and claims priority under 35 U.S.C. §119 to European Application No. 09252490.9, filed Oct. 27, 2009, theentire content of which is hereby incorporated by reference.

BACKGROUND

WO 2007/078273 discloses an electrical smoking system which uses aliquid as an aerosol forming substrate. The liquid is stored in acontainer formed of a porous material. The container communicates with aheater vaporizer, powered by a battery supply, via a series of smallapertures. In use, the heater is activated by the mouth of the user forswitching on the battery power supply. Further, suction on themouthpiece by the user causes air to be drawn through the porouscontainer for liquid, over the heater vaporizer, and into the mouthpieceand subsequently into the mouth of a user.

It is therefore an object of the invention to provide an improvedsmoking system.

SUMMARY OF SELECTED FEATURES

In a preferred embodiment, a smoking system includes a capillary wickfor holding liquid, at least one heater for heating the liquid in atleast a portion of the capillary wick to form an aerosol, at least oneair inlet, at least one air outlet and a chamber between the air inletand air outlet, the air inlet, the air outlet and the chamber beingarranged so as to define an air flow route from the air inlet to the airoutlet via the capillary wick so as to convey the aerosol to the airoutlet, and at least one guide for channeling the air flow in the airflow route, so as to control particle size in the aerosol. Preferably,the at least one guide is arranged so that the air flow speed over thewick is greater than the air flow speed upstream of the wick. Alsopreferably, the at least one guide is arranged to control the particlesize of the aerosol to have a diameter substantially less than about 1.5micrometers.

In the preferred embodiment, the smoking system also includes a housing.In one embodiment, the at least one guide for channelling the air flowis provided by the internal shape of the housing. In another embodiment,the internal shape of the housing at least partially defines the shapeof the chamber. In yet another embodiment, the housing is internallyshaped downstream of the capillary wick to form an impactor for trappinglarger aerosol particles. In still another embodiment, the at least oneguide for channelling the air flow is provided by one or more removableinserts contained in the housing. Preferably, at least one of theremovable inserts is downstream of the capillary wick and includes animpactor for trapping larger aerosol particles.

In the preferred embodiment, the capillary wick is elongate. In oneembodiment, the guides are configured to channel the air flow upstreamof the capillary wick in a direction substantially parallel to thelongitudinal axis of the capillary wick. In another embodiment, theguides are configured to channel the air flow downstream of thecapillary wick in a direction substantially parallel to the longitudinalaxis of the capillary wick. In yet another embodiment, the guides areconfigured to channel the air flow around the capillary wick in aspiral. In still another embodiment, the guides are configured tochannel the air flow onto the capillary wick in a directionsubstantially perpendicular to the longitudinal axis of the capillarywick. In another embodiment, the guides are configured to channel theair flow off the capillary wick in a direction substantiallyperpendicular to the longitudinal axis of the capillary wick. In stillanother embodiment, the guides are configured to channel the air flowoff the capillary wick in a direction substantially parallel to thelongitudinal axis of the capillary wick.

Also in the preferred embodiment, the at least one heater includes acoil of wire at least partially surrounding the capillary wick.

In another embodiment, a smoking system includes a capillary wick forholding liquid, at least one air inlet, at least one air outlet and achamber between the air inlet and air outlet, the air inlet, the airoutlet and the chamber being arranged so as to define an air flow routefrom the air inlet to the air outlet via the capillary wick so as toconvey aerosol formed from the liquid to the air outlet, and at leastone guide for channeling the air flow in the air flow route, so as tocontrol particle size in the aerosol.

In still another embodiment, an aerosol delivery system includes acapillary wick for holding liquid, at least one heater for heating theliquid in at least a portion of the capillary wick to form an aerosol,at least one air inlet, at least one air outlet and a chamber betweenthe air inlet and air outlet; the air inlet, the air outlet and thechamber being arranged so as to define an air flow route from the airinlet to the air outlet via the capillary wick so as to convey theaerosol to the air outlet, and at least one guide for channeling airflow in the air flow route, so as to control particle size in theaerosol.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be further described, by way of example only, withreference to the accompanying drawings, in which:

FIG. 1 shows one example of a smoking system having a liquid storageportion;

FIGS. 2a, 2b and 2c show a first embodiment of the smoking system;

FIGS. 3a and 3b show a second embodiment of the smoking system;

FIG. 4 shows a third embodiment of the smoking system;

FIGS. 5a and 5b show a fourth embodiment of the smoking system;

FIGS. 6a, 6b, 6c, 6d and 6e show a fifth embodiment of the smokingsystem;

FIGS. 7a, 7b and 7c show a sixth embodiment of the smoking system;

FIGS. 8a, 8b and 8c show a seventh embodiment of the smoking system;

FIGS. 9a, 9b, 9c and 9d show an eighth embodiment of the smoking system;

FIGS. 10a, 10b, 10c and 10d show a ninth embodiment of the smokingsystem; and

FIGS. 11a to 11l show a tenth embodiment of the smoking system.

DETAILED DESCRIPTION

The present invention relates to a smoking system having a liquidstorage portion. In a preferred embodiment, a smoking system includes acapillary wick for holding liquid, at least one heater for heating theliquid in at least a portion of the capillary wick to form an aerosol,at least one air inlet, at least one air outlet and a chamber betweenthe air inlet and air outlet, the air inlet, the air outlet and thechamber being arranged so as to define an air flow route from the airinlet to the air outlet via the capillary wick so as to convey theaerosol to the air outlet, and at least one guide for channeling the airflow in the air flow route, so as to control particle size in theaerosol.

In use, when the heater is activated, the liquid in the at least oneportion of the capillary wick is vaporized by the heater to form asupersaturated vapor. The supersaturated vapor is mixed with and carriedin the air flow from the at least one air inlet. During the flow, thevapor condenses to form an aerosol in the chamber, and the aerosol iscarried towards the air outlet into the mouth of a user. As used herein,the upstream and downstream relative positions are described in relationto the direction of air flow as it is drawn from the air inlet to theair outlet.

The smoking system provides a number of advantages. Most significantly,the at least one guide improves the air and aerosol flow through thesmoking system. In particular, the management of the air and aerosolflow through the smoking system by the guides allows either control ofthe air flow upstream of the capillary wick or control of the air andaerosol flow downstream of the capillary wick or both. Management of theair flow, in particular the air flow direction and the air flow speed,allows the particle size in the resulting aerosol to be controlled andpreferably reduced compared with known devices. This improves thesmoking experience. In addition, control of the air and aerosol flow canresult in higher system efficiency and resulting energy savings.

The liquid has physical properties, for example a boiling point suitablefor use in the smoking system: if the boiling point is too high, the atleast one heater will not be able to vaporize liquid in the capillarywick, but, if the boiling point is too low, the liquid may vaporize evenwithout the at least one heater being activated. The liquid preferablyincludes a tobacco-containing material including volatile tobacco flavorcompounds which are released from the liquid upon heating.Alternatively, or in addition, the liquid may include a non-tobaccomaterial. For example, the liquid may include water, solvents, ethanol,plant extracts and natural or artificial flavors. Preferably, the liquidfurther includes an aerosol former. Examples of suitable aerosol formersare glycerine and propylene glycol.

In the preferred embodiment, the smoking system further includes aliquid storage portion. Preferably, the capillary wick is arranged to bein contact with liquid in the liquid storage portion. In that case, inuse, liquid is transferred from the liquid storage portion towards theheater by capillary action in the capillary wick. In one embodiment, thecapillary wick has a first end and a second end, the first end extendinginto the liquid storage portion for contact with liquid therein and theat least one heater being arranged to heat liquid in the second end.When the heater is activated, the liquid at the second end of thecapillary wick is vaporized by the heater to form the supersaturatedvapor.

An advantage of this embodiment is that the liquid in the liquid storageportion is protected from oxygen (because oxygen cannot generally enterthe liquid storage portion via the capillary wick) and, in someembodiments light, so that the risk of degradation of the liquid issignificantly reduced. Therefore, a high level of hygiene can bemaintained. Using a capillary wick extending between the liquid and theheater, allows the structure of the system to be relatively simple. Theliquid has physical properties, including viscosity, which allow theliquid to be transported through the capillary wick by capillary action.

The liquid storage portion is preferably a container. Preferably, theliquid storage portion does not include any porous materials, so thatthere is only a single capillary mechanism (the capillary wick) in thesmoking system. This keeps the structure of the smoking system simpleand the entire system low-maintenance. Preferably, the container isopaque, thereby limiting degradation of the liquid by light. The liquidstorage portion may not be refillable. Thus, when the liquid in theliquid storage portion has been used up, the smoking system is replaced.Alternatively, the liquid storage portion may be refillable. In thatcase, the smoking system may be replaced after a certain number ofrefills of the liquid storage portion. Preferably, the liquid storageportion is arranged to hold liquid for a pre-determined number of puffs.

In the preferred embodiment, the capillary wick may have a fibrous orspongy structure. For example, the capillary wick may include aplurality of fibers or threads. The fibers or threads may be generallyaligned in the longitudinal direction of the smoking system.Alternatively, the capillary wick may include sponge-like materialformed into a rod shape. The rod shape may extend along the longitudinaldirection of the smoking system. In the preferred embodiment, thestructure of the wick forms a plurality of small bores or tubes, throughwhich the liquid can be transported to the heater, by capillary action.

Preferably, the capillary wick may include any suitable material orcombination of materials. Examples of suitable materials are ceramic- orgraphite-based materials in the form of fibers or sintered powders.Moreover, the capillary wick may have any suitable capillarity andporosity so as to be used with different liquid physical properties suchas density, viscosity, surface tension and vapor pressure. The capillaryproperties of the wick, combined with the properties of the liquid,ensure that the wick is always wet in the heating area. If the wick isdry, there may be overheating, which can lead to thermal degradation ofliquid.

Preferably, the at least one guide channels the air flow by controllingthe air flow velocity, that is to say, the speed of the air flow and thedirection of the air flow. This may be by directing the air flow in aparticular direction. Alternatively or additionally, this may be bycontrolling the speed of the air flow. The air flow speed may becontrolled by varying the cross sectional area of the air flow route, soas to take advantage of the Venturi effect. Air flow through aconstricted section increases in speed in order to satisfy the equationof continuity. Similarly, air flow through a wider section decreases inspeed.

Preferably, the at least one guide is arranged so that the air flowspeed over the wick is greater than the air flow speed upstream of thewick. This is preferably achieved by the guides defining a constrictedair flow cross section over the wick, which will force the air flow toaccelerate.

Preferably, the at least one guide is arranged to control the particlesize of the aerosol to have a diameter substantially less than about 1.5micrometers (μm). Even more preferably, the at least one guide isarranged to control the particle size of the aerosol to have a diametersubstantially less than about 1.0 micrometers (μm).

In the preferred embodiment, the smoking system can further include ahousing and the at least one guide for channelling the air flow isprovided by the internal shape of the housing. That is to say, theinternal shape of the assembly itself channels the air flow. Preferably,the inside surface of the housing walls have a shape which forms guidesto channel the air flow. The guides provided by the internal shape ofthe housing may be provided upstream of the capillary wick. In thatcase, the guides channel the air flow from the air inlet towards thecapillary wick. Alternatively or additionally, the guides provided bythe internal shape of the housing may be provided downstream of thecapillary wick. In that case, the guides channel the aerosol and airflow from the capillary wick towards the air outlet. In the preferredembodiment, the internal shape of the housing defines a tapered channeltowards the air outlet.

In another embodiment, the internal shape of the housing may define alinear flow upstream or downstream of the capillary wick. Alternatively,the internal shape of the housing may define a swirled, that is to say,rotating or spiralling, flow upstream or downstream of the capillarywick. In yet another embodiment, the internal shape of the housing maydefine any turbulent flow upstream or downstream of the capillary wick.

In the preferred embodiment, the smoking system may also include ahousing and the internal shape of the housing may at least partiallydefine the shape of the chamber. The size and shape of the chamberaffects the air and aerosol flow from the capillary wick towards the airoutlet, which affects the process of aerosol formation. This affects thesize of the particles in the aerosol. For example, if the chamber issmall, this will encourage a fast movement of the aerosol particlestowards the air outlet. On the other hand, if the chamber is larger,this may allow more time for the aerosol to form and flow towards theair outlet. The chamber may surround the capillary wick or may bedownstream of the capillary wick. The position of the chamber relativeto the capillary wick also affects the size of the particles in theaerosol. This is because this affects how quickly the vapor condenses toform the aerosol.

In another embodiment, the smoking system includes a housing and thehousing is internally shaped downstream of the capillary wick to form animpactor for trapping larger aerosol particles. Larger aerosol particlesmay be those aerosol particles which have a diameter greater than about1.5 micro meters. Alternatively, larger aerosol particles may be thoseaerosol particles which have a diameter greater than about 1.0 micrometers. Alternatively, larger aerosol particles may include thoseaerosol particles having another size. The greater inertia of the largeraerosol particles means that, if the air flow route includes a suddenchange in direction, the larger aerosol particles may not be able tochange direction sufficiently quickly to remain in the air flow routeand may, instead, be trapped by the impactor. The impactor is preferablypositioned to take advantage of the greater momentum of the largeraerosol particles.

Preferably, the position of the impactor, for example relative to thecapillary wick and heater and relative to the chamber, will affect thesize and number of particles which are trapped. If the smoking systemincludes an impactor, the at least one guide may include an accelerationnozzle for directing the aerosol towards the impactor. The nozzle maydefine a decreasing cross sectional area of the air flow route, so as toaccelerate the aerosol towards the impactor. Larger aerosol particlesbecome trapped on the impactor, whereas the smaller aerosol particlescan divert around the impactor in the flow route.

In another embodiment, the smoking system further includes a housing,and the at least one guide for channelling the air flow is provided byone or more removable inserts contained in the housing. The one or moreremovable inserts may include a removable insert upstream of thecapillary wick. In that case, the guides channel the air flow from theair inlet towards the capillary wick and heater. Alternatively oradditionally, the one or more removable inserts may include a removableinsert downstream of the capillary wick. In that case, the guideschannel the aerosol and air flow from the capillary wick and heatertowards the air outlet. The one or more removable inserts may channelthe air flow directly on to the capillary wick and heater. The one ormore removable inserts may channel the air flow directly off thecapillary wick and heater.

Preferably, the one or more removable inserts may define a linear flowupstream or downstream of the capillary wick and heater. The one or moreremovable inserts may define a swirled, that is to say, rotating orspiralling, flow upstream or downstream of the capillary wick. The oneor more removable inserts may define any turbulent flow upstream ordownstream of the capillary wick.

The one or more removable inserts may at least partially define theshape of the chamber. Usually, this will be in combination with theinternal shape of the housing, but that is not necessarily the case. Thesize and shape of the chamber affects the air and aerosol flow from thecapillary wick and heater towards the air outlet. This affects the sizeof the particles in the aerosol. The chamber may surround the capillarywick and heater or may be downstream of the capillary wick and heater.The position of the chamber relative to the capillary wick and heateralso affects the size of the particles in the aerosol.

In one embodiment, the one or more removable inserts includes aremovable insert surrounding the capillary wick and heater. In thatcase, preferably the removable insert defines the flow route directly onto the capillary wick and heater and directly off the capillary wick andheater. In one embodiment, the capillary wick is elongate and theremovable insert directs the air flow on to the capillary wick in adirection substantially perpendicular to the longitudinal axis of thecapillary wick and directs the air flow off the capillary wick in adirection substantially parallel to the longitudinal axis of thecapillary wick. Preferably, the smoking system includes an elongatehousing and the longitudinal axis of the capillary wick and thelongitudinal axis of the housing are substantially parallel. In anotherembodiment, the capillary wick is elongate and the removable insertdirects the air flow on to the capillary wick in a directionsubstantially perpendicular to the longitudinal axis of the capillarywick and directs the air flow off the capillary wick in a directionsubstantially perpendicular to the longitudinal axis of the capillarywick. In that case, the air flow on to the capillary wick may besubstantially perpendicular to the air flow off the capillary wick.Alternatively, the air flow on to the capillary wick may besubstantially in the same direction as the air flow off the capillarywick. Again, preferably, the smoking system includes an elongate housingand the longitudinal axis of the capillary wick and the longitudinalaxis of the housing are substantially parallel.

Preferably, at least one of the removable inserts includes bores forchannelling the air flow therethrough. The bores may be formed in theinsert by machining or, alternatively, by injection molding.

In one embodiment, at least one of the removable inserts is downstreamof the capillary wick and includes an impactor for trapping largeraerosol particles. Larger aerosol particles may be those aerosolparticles which have a diameter greater than about 1.5 micrometers.Alternatively, larger aerosol particles may be those aerosol particleswhich have a diameter greater than about 1.0 micrometers. Alternatively,larger aerosol particles may include those aerosol particles havinganother size. The greater inertia of the larger aerosol particles meansthat, if the air flow route includes a sudden change in direction, thelarger aerosol particles may not be able to change directionsufficiently quickly to remain in the air flow route and may, instead,be trapped by the impactor. The impactor is preferably positioned totake advantage of the greater momentum of the larger aerosol particles.

For example, the removable insert may include a plate positioneddownstream of the capillary wick for trapping larger aerosol particleswhich come into contact with the plate. The plate may be positionedsubstantially perpendicular to the air flow route. The position of theimpactor, for example relative to the capillary wick and heater andrelative to the chamber, will affect the size and number of particleswhich are trapped.

If the smoking system includes an impactor, the at least one guide mayinclude an acceleration nozzle for directing the aerosol towards theimpactor. The nozzle may define a decreasing cross sectional area of theair flow route, so as to accelerate the aerosol towards the impactor.Larger aerosol particles become trapped on the impactor, whereas thesmaller aerosol particles can divert around the impactor in the flowroute.

In the preferred embodiment, the one or more removable inserts maycontain any of the liquid storage portion, the capillary wick and theheater. If a removable insert contains the liquid storage portion, thecapillary wick and the heater, those parts of the smoking system may beremovable from the housing as a single component. This may be useful forrefilling or replacing the liquid storage portion, for example.

The guides may be provided by additional components positioned in theflow route. For example, the smoking system may further include pins,grills, perforated tubes, or any other component which may affect theflow route.

In one embodiment, the capillary wick is elongate and the guides areconfigured to channel the air flow upstream of the capillary wick in adirection substantially parallel to the longitudinal axis of thecapillary wick. In that embodiment, the smoking system may be elongatein shape, with the longitudinal axis of the capillary wick beingsubstantially parallel to the longitudinal axis of the smoking system.

In another embodiment, the capillary wick is elongate and the guides areconfigured to channel the air flow downstream of the capillary wick in adirection substantially parallel to the longitudinal axis of thecapillary wick. In that embodiment, the smoking system may be elongatein shape, with the longitudinal axis of the capillary wick beingsubstantially parallel to the longitudinal axis of the smoking system.

In one embodiment, the guides are configured to channel the air flowaround the capillary wick in a spiral. In that case, the air may enterthe spiral in a tangential direction. The air may exit the spiral in atangential direction. In that embodiment, the capillary wick may beelongate in shape and the spiral may have an axis which is substantiallythe longitudinal axis of the capillary wick. The smoking system may beelongate in shape, with the longitudinal axis of the capillary wickbeing substantially parallel to the longitudinal axis of the smokingsystem.

In yet another embodiment, the capillary wick is elongate and the guidesare configured to channel the air flow onto the capillary wick in adirection substantially perpendicular to the longitudinal axis of thecapillary wick. In that embodiment, the smoking system may be elongatein shape, with the longitudinal axis of the capillary wick beingsubstantially parallel to the longitudinal axis of the smoking system.

Alternatively, the guides may be configured to channel the air flow ontothe capillary wick in a direction intermediate between the direction ofthe longitudinal axis of the capillary wick and the directionperpendicular to the longitudinal axis of the capillary wick. That is tosay, the guides may channel the air flow onto the capillary wick at anon-90° angle to the capillary wick, that is to say, in a diagonaldirection.

In one embodiment, the capillary wick is elongate and the guides areconfigured to channel the air flow off the capillary wick in a directionsubstantially perpendicular to the longitudinal axis of the capillarywick. In that embodiment, the smoking system may be elongate in shape,with the longitudinal axis of the capillary wick being substantiallyparallel to the longitudinal axis of the smoking system.

In another embodiment, the capillary wick is elongate and the guides areconfigured to channel the air flow off the capillary wick in a directionsubstantially parallel to the longitudinal axis of the capillary wick.In that embodiment, the smoking system may be elongate in shape, withthe longitudinal axis of the capillary wick being substantially parallelto the longitudinal axis of the smoking system.

Alternatively, the guides may be configured to channel the air flow offthe capillary wick in a direction intermediate between the direction ofthe longitudinal axis of the capillary wick and the directionperpendicular to the longitudinal axis of the capillary wick. That is tosay, the guides may channel the air flow off the capillary wick at anon-90° angle to the capillary wick, that is to say, in a diagonaldirection.

In the preferred embodiment, the at least one heater may include asingle heating element. Alternatively, the at least one heater mayinclude more than one heating element, for example two, three, four,five, six or more heating elements. The heating element or heatingelements may be arranged appropriately so as to most effectivelyvaporize liquid in the capillary wick.

The at least one heater preferably includes an electrical heatingelement. The at least one heater preferably includes an electricallyresistive material. Suitable electrically resistive materials includebut are not limited to: semiconductors such as doped ceramics,electrically “conductive” ceramics (such as, for example, molybdenumdisilicide), carbon, graphite, metals, metal alloys and compositematerials made of a ceramic material and a metallic material. Suchcomposite materials may include doped or undoped ceramics.

Examples of suitable doped ceramics include doped silicon carbides.

Examples of suitable metals include titanium, zirconium, tantalum andmetals from the platinum group. Examples of suitable metal alloysinclude stainless steel, Constantan, nickel-, cobalt-, chromium-,aluminium-titanium-zirconium-, hafnium-, niobium-, molybdenum-,tantalum-, tungsten-, tin-, gallium-, manganese- and iron-containingalloys, and super-alloys based on nickel, iron, cobalt, stainless steel,Timetal® and iron-manganese-aluminium based alloys. Timetal® is aregistered trade mark of Titanium Metals Corporation, 1999 BroadwaySuite 4300, Denver Colo. In composite materials, the electricallyresistive material may optionally be embedded in, encapsulated or coatedwith an insulating material or vice-versa, depending on the kinetics ofenergy transfer and the external physicochemical properties required.

The at least one heater may take any suitable form. For example, the atleast one heater may take the form of a heating blade. Alternatively,the at least one heater may take the form of a casing or substratehaving different electro-conductive portions, or an electricallyresistive metallic tube. Alternatively, the at least one heater may be adisk (end) heater or a combination of a disk heater with heating needlesor rods. Alternatively, the at least one heater may take the form of ametallic etched foil insulated between two layers of an inert material.In that case, the inert material may include Kapton, all-polyimide ormica foil. Alternatively, the at least one heater may take the form of asheet of material, which may be rolled around at least a portion of thecapillary wick. Alternatively, the at least one heater may take the formof an etched foil folded around at least a portion of the capillarywick. The etched foil may include a metal sheet cut by a laser or byelectro-chemical process. The sheet may be made from any suitablematerial, for example an iron-aluminium based alloy, aniron-manganese-aluminium base alloy or Timetal@. The sheet may berectangular in shape, or may have a patterned shape which may form acoil-like structure when rolled around the capillary wick. Otheralternatives include a heating wire or filament, for example a Ni—Cr,platinum, tungsten or alloy wire.

In one embodiment, the at least one heater includes a coil of wire atleast partially surrounding the capillary wick. In that embodiment,preferably the wire is a metal wire. Even more preferably, the wire is ametal alloy wire. The coil may extend fully or partially along thelength of the capillary wick. The coil may extend fully or partiallyaround the circumference of the capillary wick. In another embodiment,the coil is not in contact with the capillary wick. This allows theheating coil to heat the capillary wick but reduces wastage by notvaporizing more liquid than necessary. This also reduces the amount ofliquid which condenses on the inside walls, thereby reducing cleaningrequirements.

Preferably, the at least one heater may heat the liquid in the capillarywick by means of conduction. The heater may be at least partially incontact with the wick. Alternatively, heat from the heater may beconducted to the liquid by means of a heat conductive element.Alternatively, the at least one heater may transfer heat to the incomingambient air that is drawn through the smoking system during use, whichin turn heats the liquid by convection. The ambient air may be heatedbefore passing through the system. Alternatively, the ambient air may befirst drawn through the wick and then heated.

In one embodiment, the smoking system is an electrically heated smokingsystem. In that embodiment, the smoking system may further include anelectric power supply. Preferably, the electric power supply includes acell contained in a housing. The electric power supply may be aLithium-ion battery or one of its variants, for example a Lithium-ionpolymer battery. Alternatively, the power supply may be a Nickel-metalhydride battery, a Nickel cadmium battery, a Lithium-manganese battery,a Lithium-cobalt battery or a fuel cell. In that case, preferably, theelectrically heated smoking system is usable by a smoker until theenergy in the power cell is used up. Alternatively, the electric powersupply may include circuitry chargeable by an external charging portion.In that case, preferably the circuitry, when charged, provides power fora pre-determined number of puffs, after which the circuitry must bere-connected to the external charging portion. An example of suitablecircuitry is one or more capacitors or rechargeable batteries.

If the smoking system is an electrically heated smoking system, thesmoking system may further include electric circuitry. In oneembodiment, the electric circuitry includes a sensor to detect air flowindicative of a user taking a puff. The sensor may be anelectro-mechanical device. Alternatively, the sensor may be any of: amechanical device, an optical device, an opto-mechanical device, a microelectro mechanical systems (MEMS) based sensor and an acoustic sensor.In that case, preferably, the electric circuitry is arranged to providean electric current pulse to the at least one heater when the sensorsenses a user taking a puff. Preferably, the time-period of the electriccurrent pulse is pre-set, depending on the amount of liquid desired tobe vaporized. The electric circuitry is preferably programmable for thispurpose.

Alternatively, the electric circuitry may include a manually operableswitch for a user to initiate a puff. The time-period of the electriccurrent pulse is preferably pre-set depending on the amount of liquiddesired to be vaporized. The electric circuitry is preferablyprogrammable for this purpose.

In one embodiment, the at least one air inlet includes two air inlets.Alternatively, there may be three, four, five or more air inlets.Preferably, if there is more than one air inlet, the air inlets arespaced around the housing. In the preferred embodiment, the electriccircuitry includes a sensor to detect air flow indicative of a usertaking a puff, and the at least one air inlet upstream of the sensor.

Preferably, the smoking system further includes a puff indicator forindicating when the at least one heater is activated. In the embodimentin which the electric circuitry includes a sensor to detect air flowindicative of a user taking a puff, the indicator may be activated whenthe sensor senses air flow indicative of the user taking a puff. In theembodiment in which the electric circuitry includes a manually operableswitch, the indicator may be activated by the switch.

The electrically heated smoking system may further include an atomizerincluding the at least one heater. In addition to a heating element, theatomizer may include one or more electromechanical elements such aspiezoelectric elements. Additionally or alternatively, the atomizer mayalso include elements that use electrostatic, electromagnetic orpneumatic effects.

Preferably, the smoking system includes a housing. The housing mayinclude a shell and a mouthpiece. In that case, all the components maybe contained in either the shell or the mouthpiece. In the case of anelectrically heated smoking system, preferably, the electric powersupply and the electric circuitry are contained in the shell.Preferably, the liquid storage portion, the capillary wick, the at leastone heater and the air outlet are contained in the mouthpiece. The atleast one air inlet may be provided in either the shell or themouthpiece. The guides may be provided in either the shell or themouthpiece or both the shell and the mouthpiece. Preferably, themouthpiece is replaceable. Having a shell and a separate mouthpieceprovides a number of advantages. First, if the replaceable mouthpiececontains the at least one heater, the liquid storage portion and thewick, all elements which are potentially in contact with the liquid arechanged when the mouthpiece is replaced. There will be nocross-contamination in the shell between different mouthpieces, forexample ones using different liquids. Also, if the mouthpiece isreplaced at suitable intervals, there is little chance of the heaterbecoming clogged with liquid. Preferably, the shell and mouthpiece arearranged to releasably lock together when engaged.

The housing may include any suitable material or combination ofmaterials. Examples of suitable materials include metals, alloys,plastics or composite materials containing one or more of thosematerials, or thermoplastics that are suitable for food orpharmaceutical applications, for example polypropylene,polyetheretherketone (PEEK) and polyethylene. Preferably, the materialis light and non-brittle.

Preferably, the smoking system is portable. The smoking system may havea size comparable to a conventional cigar or cigarette.

In one embodiment, a smoking system includes a capillary wick forholding liquid, at least one air inlet, at least one air outlet and achamber between the air inlet and air outlet, the air inlet, the airoutlet and the chamber being arranged so as to define an air flow routefrom the air inlet to the air outlet via the capillary wick so as toconvey aerosol formed from the liquid to the air outlet, and at leastone guide for channeling the air flow in the air flow route, so as tocontrol particle size in the aerosol.

In that case, the smoking system may include an atomizer to create theaerosol. The atomizer may include one or more electromechanical elementssuch as piezoelectric elements. Additionally or alternatively, theatomizer may also include elements that use electrostatic,electromagnetic or pneumatic effects.

Features described in relation to one embodiment of the invention mayalso be applicable to another embodiment of the invention.

FIG. 1 shows one example of a smoking system 100 having a liquid storageportion. The smoking system 100 of FIG. 1 is an electrically heatedsmoking system and includes a housing 101 having a mouthpiece end 103and a body end 105. In the body end 105, there is provided an electricpower supply in the form of battery 107 and electric circuitry in theform of circuitry 109 and a puff detection system 111. In the mouthpieceend 103, there is provided a liquid storage portion in the form ofcartridge 113 containing liquid 115, a capillary wick 117 and a heatingelement in the form of heating coil 119. One end of the capillary wick117 extends into the cartridge 113 and the other end of the capillarywick 117 is surrounded by the heating coil 119. The heating coil 119 isconnected to the electric circuitry via connections 121. The housing 101also includes an air inlet 123, an air outlet 125 at the mouthpiece end103 and a chamber in the form of aerosol forming chamber 127.

In use, operation is as follows. Liquid 115 is transferred by capillaryaction from the cartridge 113 from the end of the wick 117 which extendsinto the cartridge to the other end of the wick 117 which is surroundedby the heating coil 119. When a user draws on the device at the airoutlet 125, ambient air is drawn through air inlet 123. In FIG. 1, thepuff detection system 111 senses the puff and activates the heating coil119. The battery 107 supplies a pulse of energy to the heating coil 119to heat the end of the wick 117 surrounded by the heating coil 119. Theliquid in that end of the wick 117 is vaporized by the heating coil 119to create a supersaturated vapor. At the same time, the liquid beingvaporized is replaced by further liquid moving along the wick 117 bycapillary action. (This is sometimes referred to as “pumping action”.)The supersaturated vapor created is mixed with and carried in the airflow from the air inlet 123. In the aerosol forming chamber 127, thevapor condenses to form an inhalable aerosol, which is carried towardsthe outlet 125 and into the mouth of the user.

As shown in FIG. 1, the circuitry 109 and the puff detection system 111are preferably programmable. The circuitry 109 and puff detection system111 can be used to manage the device operation. This, in conjunctionwith the physical design of the electrically heated smoking system, canassist with control of the particle size in the aerosol.

The capillary wick can be made from a variety of porous or capillarymaterials and preferably has a known, pre-defined capillarity. Examplesinclude ceramic- or graphite-based materials in the form of fibers orsintered powders. Wicks of different porosities can be used toaccommodate different liquid physical properties such as density,viscosity, surface tension and vapor pressure. The wick must be suitableso that the required amount of liquid can be delivered to the heatingcoil.

FIG. 1 shows one example of a smoking system which may be used with thepresent invention. Many other examples are usable with the invention,however. For example, the smoking system need not be electricallyoperated. For example, additional air inlets may be provided, forexample, spaced circumferentially around the housing. For example, apuff detection system need not be provided. Instead, the system couldoperate by manual operation, for example, the user operating a switchwhen a puff is taken. For example, the housing could include a separableshell and mouthpiece. For example, the overall shape and size of thehousing could be altered. For example, the liquid cartridge may beomitted and the capillary wick could simply be pre-loaded with liquidbefore use. Other variations are, of course, possible.

A number of embodiments will now be described, based on the exampleshown in FIG. 1. Components shown in FIG. 1 are not indicated again, inorder to simplify the drawings. In addition, the puff detection system111 and connections 121 are not shown, again for simplicity. Note thatFIG. 1 and the following FIGS. 2a to 11l are schematic in nature. Inparticular, the components shown are not to scale either individually orrelative to one another.

FIGS. 2a, 2b and 2c illustrate a first embodiment of the smoking system.FIG. 2a shows a cross sectional view of the mouthpiece end of the firstembodiment of the smoking system 200. In FIG. 2a , the smoking system200 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided in removable insert201 and in the housing inside walls 203. The air flow is shown by thedotted arrows.

Preferably, the removable insert 201 extends across the entire crosssection of the smoking system 200 and includes channels 205 forchannelling the air flow between the air inlet and the capillary wickand heating coil. In this embodiment, the liquid cartridge, thecapillary wick and the heating coil all form part of the removableinsert 201, although this need not be the case. The channels 205 taperinward to direct the air flow generally in the direction of thelongitudinal axis of the housing but diagonally towards the capillarywick and heating coil.

In addition, the housing inside walls 203 are shaped to form the aerosolforming chamber 202 and provide guides for channelling the air andaerosol flow between the capillary wick and heating coil and the airoutlet, through the aerosol forming chamber 202. In this embodiment, thehousing inside walls 203 are tapered towards the air outlet, therebydirect the air and aerosol flow substantially in the direction of thelongitudinal axis of the housing.

FIGS. 2b and 2c are cross sections along line A-A of FIG. 2a . FIGS. 2band 2c show two alternative arrangements for the channels 205 inremovable insert 201. Although the cross section of the device is shownas circular in FIGS. 2a, 2b and 2c , this need not be the case. In FIG.2b , the inlet of each channel is circumferentially aligned with theoutlet of the channel. In FIG. 2c , the channels 205 are twisted aroundthe axis of the housing. That is to say, the inlet of each channel isshifted circumferentially with respect to the outlet of the channel.Preferably, the insert 201 includes a locating pin or protrusion (notshown) on its outer surface for cooperating with a recess (also notshown) on the inside of the housing walls, so as to ensure that theinsert is correctly positioned within the smoking system. This may beimportant for the electrical connections to the heating coil, forexample.

The embodiment shown in FIGS. 2a, 2b and 2c provides a substantiallyaxially directed incoming air flow from the air inlet to the capillarywick and heating coil and a substantially axially directed outgoing airflow from the capillary wick and heating coil to the air outlet. It hasbeen found that managing the air flow in this way improves the aerosolformation occurring within the smoking system. The guides provided byinsert 201 channel the air flow so as to concentrate air flow onto thewick and heating element and so as to increase turbulence. Thisdecreases the particle size of the aerosol inhaled by a user. The guidesprovided by the housing inside walls 203 reduce the volume of theaerosol forming chamber 202 in the smoking system and therefore improveaerosol flow towards the air outlet. This improves the smokingexperience. The arrangement of FIG. 2c encourages a swirled airflow toimprove aerosol formation even further.

A number of variations are possible in the smoking system of FIGS. 2a,2b and 2c . First, more than one air inlet may be provided. The guidesupstream of the capillary wick and heating coil may be formed as one ormore removable portions (insert 201, as shown) or alternatively as anintegral part of the housing or as a combination of both. Similarly, theguides downstream of the capillary wick and heating coil may be formedas one or more removable portions or alternatively as an integral partof the housing (shaped housing inside walls 203, as shown) or as acombination of both. Any number of channels 205 may be formed in theinsert 201. The channels may be evenly or non-evenly distributedcircumferentially around the insert. The channels may be arranged asseveral rows forming circles of different diameters. The channels mayhave a constant cross sectional shape and area along their length, orthe cross sectional shape can vary along the length. The channels mayinclude some channels having different cross sectional shapes and areasfrom others. The channels may be formed in the insert by machining.Alternatively, the insert may be formed together with the channels byinjection molding. The channels may be formed at any appropriate angleto the longitudinal axis of the housing. The housing inside walls 203may be shaped appropriately for the desired volume and shape of theaerosol forming chamber 202 within the smoking system.

FIGS. 3a and 3b show a second embodiment of the smoking system. FIG. 3ashows a cross sectional view of the mouthpiece end of the secondembodiment of the smoking system 300. In FIG. 3a , the smoking system300 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided in removable insert301 and in the housing inside walls 303. The air flow is shown by thedotted arrows.

Just like removable insert 201 in FIGS. 2a, 2b and 2c , removable insert301 of FIGS. 3a and 3b extends across the entire cross section of thesmoking system. However, in this embodiment, it also extends furtherupstream than the insert 201 of FIGS. 2a, 2b and 2c . The removableinsert 301 includes channels 305 for channelling the air flow betweenthe air inlet and the capillary wick and heating coil. The channels 305extend in the direction of the longitudinal axis of the housing at theirupstream end, then taper inward at their downstream end. The channels305 direct the air flow generally in the direction of the longitudinalaxis of the housing initially, then diagonally towards the capillarywick and heating coil. In this embodiment, the liquid cartridge, thecapillary wick and the heating coil all form part of the removableinsert 301, although this need not be the case.

In addition, the housing inside walls 303 are shaped to form the aerosolforming chamber 302 and to provide guides for channelling the air andaerosol flow between the capillary wick and heating coil and the airoutlet, through the aerosol forming chamber 302. In this embodiment, thehousing inside walls 303 are tapered towards the air outlet and therebydirect the air and aerosol flow substantially in the direction of thelongitudinal axis of the housing.

FIG. 3b is a cross section along line B-B of FIG. 3a . Although thecross section of the device is shown as circular in FIG. 3b , this neednot be the case. Referring to FIG. 3b , the insert 301 includes channels305. Around the circumference of the insert 301 are several contactzones 307 for contacting with the inside of the housing. That is to say,the channels are formed by assembly of the insert in the housing.Preferably, the insert 301 includes a locating pin or protrusion (notshown) on its outer surface for cooperating with a recess (also notshown) on the inside of the housing walls, so as to ensure that theinsert is correctly positioned within the smoking system. This may beimportant for the electrical connections to the heating coil, forexample.

The embodiment shown in FIGS. 3a and 3b provides a substantially axiallydirected incoming air flow from the air inlet to the capillary wick andheating coil and a substantially axially directed outgoing air flow fromthe capillary wick and heating coil to the air outlet. It has been foundthat managing the air flow in this way improves the aerosol formationoccurring within the smoking system. The guides provided by insert 301channel the air flow so as to concentrate air flow onto the wick andheating element and so as to increase turbulence. This decreases theparticle size of the aerosol inhaled by a user. The guides provided bythe housing inside walls 303 reduce the volume of the aerosol formingchamber 302 in the smoking system and therefore improve aerosol flowtowards the air outlet. This improves the smoking experience.

A number of variations are possible in the smoking system of FIGS. 3aand 3b . First, more than one air inlet may be provided. The guidesupstream of the capillary wick and heating coil may be formed as one ormore removable portions (insert 301, as shown) or alternatively as anintegral part of the assembly or as a combination of both. Similarly,the guides downstream of the capillary wick and heating coil may beformed as one or more removable portions or alternatively as an integralpart of the assembly (shaped housing inside walls 303, as shown) or as acombination of both. Any number of channels 305 may be formed in theinsert 301. The channels may be evenly or non-evenly distributedcircumferentially around the insert. The channels may be arranged asseveral rows forming circles of different diameters. The channels mayhave a constant cross sectional shape and area along their length, orthe cross sectional shape can vary along the length. The channels mayinclude some channels having different cross sectional shapes and areasfrom others. The channels may be formed in the insert by machining.Alternatively, the insert may be formed together with the channels byinjection molding. The channels may be formed at any appropriate angleto the longitudinal axis of the housing. As in FIG. 2c , the channelsmay be twisted around the axis of the housing, so as to encourage aswirled airflow. The housing inside walls 303 may be shapedappropriately for the desired volume and shape of the aerosol formingchamber 302 within the smoking system.

FIG. 4 shows a cross sectional view of the mouthpiece end of the thirdembodiment of the smoking system 400. In FIG. 4, the smoking system 400includes guides for channelling the air flow within the smoking system.In this embodiment, the guides are provided by removable insert 401, bythe housing inside walls 403 and by impactor 405. The air flow is shownby the dotted arrows.

The removable insert 401 is similar to removable insert 301 shown inFIGS. 3a and 3b and extends across the entire cross section of thesmoking system 400. The removable insert 401 includes channels 407 forchannelling the air flow between the air inlet and the capillary wickand heating coil. The channels 407 extend in the direction of thelongitudinal axis of the housing at their upstream end, then taperinward at their downstream end. The channels 407 direct the air flowgenerally in the direction of the longitudinal axis of the housinginitially, then diagonally towards the capillary wick and heating coil.In this embodiment, the liquid cartridge, the capillary wick and theheating coil all form part of the removable insert 401, although thisneed not be the case. Preferably, the insert 401 includes a locating pinor protrusion (not shown) on its outer surface for cooperating with arecess (also not shown) on the inside of the housing walls, so as toensure that the insert is correctly positioned within the smokingsystem. This may be important for the electrical connections to theheating coil, for example. The insert could alternatively take the formshown in FIG. 2a or another suitable form.

In addition, the housing inside walls 403 and impactor 405 provideguides for channelling the aerosol flow between the capillary wick andheating coil and the air outlet. The housing inside walls 403 andimpactor 405 also form the aerosol forming chamber 402. In thisembodiment, the housing inside walls are shaped so as to direct the flowaway from the heating coil in the radial direction, that is to say,substantially perpendicular to the longitudinal axis of the housing.Preferably, the impactor 405 includes a removable insert which may bepositioned in the center of the device, supported by the housing walls(see dotted lines). The impactor 405 allows larger aerosol particles tobe trapped on its upstream side. This produces a filtering effect andreduces the average particle size. This is shown schematically in FIG.4. Then, the housing inside walls 403 and impactor 405 direct the airflow towards the air outlet.

The embodiment shown in FIG. 4 also provides a substantially axiallydirected incoming air flow from the air inlet to the capillary wick andheating coil and a substantially radially directed air flow downstreamof the capillary wick and heating coil. It has been found that managingair flow in this way improves the aerosol formation occurring within thesmoking system. The guides provided by insert 401 channel the air flowso as to concentrate air flow onto the wick and heating element and soas to increase turbulence. This decreases the particle size of theaerosol inhaled by a user. The guides provided by the housing insidewalls 403 and impactor allow larger aerosol particles to be trapped andprevented from exiting through the air outlet. The arrangement allowsthe capillary wick and heating coil to be supplied with cool,non-saturated air, in order to decrease the aerosol particle size. Thisimproves the smoking experience.

A number of variations are possible in the smoking system of FIG. 4.First, although the cross section of the device is shown as circular inFIG. 4, this need not be the case. Second, more than one air inlet maybe provided. The guides upstream of the capillary wick and heating coilmay be formed as one or more removable portions (insert 401, as shown)or alternatively as an integral part of the housing or as a combinationof both. Similarly, the guides downstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing or as a combination ofboth (shaped housing inside walls 403 combined with removable impactor405, as shown). Any number of channels 407 may be formed in the insert401. The channels may be evenly or non-evenly distributedcircumferentially around the insert. The channels may be arranged asseveral rows forming circles of different diameters. The channels mayhave a constant cross sectional shape and area along their length, orthe cross sectional shape can vary along the length. The channels mayinclude some channels having different cross sectional shapes and areasfrom others. The channels may be formed in the insert by machining.Alternatively, the insert may be formed with the channels by injectionmolding. The channels may be formed at any appropriate angle to thelongitudinal axis of the housing. As in FIG. 2c , the channels may betwisted around the axis of the housing, so as to encourage a swirledairflow. The housing inside walls 403 and impactor 405 may be shaped andsized appropriately for the desired volume and shape of the aerosolforming chamber 402 within the smoking system. The impactor 405 may beformed with any appropriate shape and is preferably designed inconjunction with the shaped housing inside walls 403, in order tochannel the air and aerosol flow as desired.

FIGS. 5a and 5b show a fourth embodiment of the smoking system. FIG. 5ashows a cross sectional view of the mouthpiece end of the fourthembodiment of the smoking system 500. In FIG. 5a , the smoking system500 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided by removable insert501, by the housing inside walls 503 and by impactor 505.

The removable insert 501 is similar to removable insert 201 shown inFIGS. 2a, 2b and 2c , extends across the entire cross section of thesmoking system 500, and includes channels 507 for channelling the airflow between the air inlet and the capillary wick and heating coil. Inthis embodiment, the liquid cartridge, the capillary wick and heatingcoil all form part of the removable insert 501, although this need notbe the case. The channels 507 taper inward to direct the air flowgenerally in the direction of the longitudinal axis of the housing butdiagonally towards the capillary wick and heating coil. Preferably, theinsert 501 includes a locating pin or protrusion (not shown) on itsouter surface for cooperating with a recess (also not shown) on theinside of the housing walls, so as to ensure that the insert iscorrectly positioned within the smoking system. This may be importantfor the electrical connections to the heating coil, for example. Theinsert could alternatively take the form shown in FIGS. 3a and 4 oranother suitable form.

In addition, the housing inside walls 503 are tapered inward to form theaerosol forming chamber 502. The housing inside walls 503 together withthe impactor 505 provide guides for channelling the aerosol flow betweenthe capillary wick and heating coil and the air outlet. In thisembodiment, the housing inside walls 503 are shaped so as to form anozzle to direct and accelerate the air flow substantially in the axialdirection. Preferably, impactor 505 is located directly downstream ofthe aerosol forming chamber.

FIG. 5b is a cross section along line C-C of FIG. 5a . The impactor 505acts to trap larger aerosol particles and therefore provides a filteringeffect. The impactor 505 includes a plate 505 a which may be positionedin the center of the housing, supported at the housing walls by struts505 b. The plate 505 a acts to trap the larger aerosol particles exitingthe aerosol forming chamber 502.

The embodiment shown in FIGS. 5a and 5b provides an accelerated,substantially axially directed air flow downstream of the capillary wickand heating coil. It has been found that managing the air flow in thisway improves the aerosol formation occurring within the smoking system.The guides provided by insert 501 channel the air flow so as toconcentrate air flow onto the wick and heating element and so as toincrease turbulence. This decreases the particle size of the aerosolinhaled by a user. The tapered nozzle shape provided by the housinginside walls 503 accelerate the aerosol downstream towards the impactor505 and the plate 505 a of the impactor 505 traps larger aerosolparticles to prevent them exiting through the air outlet. Thearrangement allows the capillary wick and heating coil to be suppliedwith cool, non-saturated air, in order to decrease the aerosol particlesize. It also allows any larger aerosol particles that do form to befiltered out of the flow. This improves the smoking experience.

A number of variations are possible in the smoking system of FIGS. 5aand 5b . First, although the cross section of the device is shown ascircular in FIGS. 5a and 5b , this need not be the case. Second, morethan one air inlet may be provided. The guides upstream of the capillarywick and heating coil may be formed as one or more removable portions(insert 501, as shown) or alternatively as an integral part of thehousing or as a combination of both. Similarly, the guides downstream ofthe capillary wick and heating coil may be formed as one or moreremovable portions or alternatively as an integral part of the housingor as a combination of both (shaped housing inside walls 503 combinedwith removable impactor 505, as shown). Any number of channels 507 maybe formed in the insert 501. The channels may be evenly or non-evenlydistributed circumferentially around the insert. The channels may bearranged as several rows forming circles of different diameters. Thechannels may have a constant cross sectional shape and area along theirlength, or the cross sectional shape can vary along the length. Thechannels may include some channels having different cross sectionalshapes and areas from others. The channels 507 may be twisted around theaxis of the housing to provide a swirled air flow. The channels may beformed in the insert by machining. Alternatively, the insert may beformed together with the channels by injection molding. The channels maybe formed at any appropriate angle to the longitudinal axis of thehousing.

The housing inside walls 503 may be shaped appropriately for the desiredvolume and shape of the aerosol forming chamber 502 within the smokingsystem and for the desired acceleration of the aerosol towards theimpactor 505. The impactor may be formed by machining or injectionmolding. The shape and size of the impactor plate 505 a may be varied.The distance between the downstream end of the aerosol forming chamber502 and the impactor plate may be varied.

FIGS. 6a to 6e each show a cross sectional view of the mouthpiece end ofa fifth embodiment of the smoking system. In each of FIGS. 6a to 6e ,the smoking system includes guides for channelling the air flow withinthe smoking system. The air flow is shown by the dotted arrows.

FIG. 6a shows a first arrangement of the smoking system 600. In FIG. 6a, the guides are provided by removable insert 601 and by the housinginside walls 603. The removable insert 601 extends only across thecenter of the smoking system 600, thereby directing the air flow betweenthe air inlet and the capillary wick and heating coil to the outercircumference of the device. The removable insert 601 is shaped so that,at the capillary wick and heating coil, the air flow is directed ontothe capillary wick and heating coil in a substantially radial direction,that is to say, substantially perpendicular to the longitudinal axis ofthe housing. In FIGS. 6a to 6e , the liquid cartridge, the capillarywick and the heating coil all form part of the removable insert 601,although this need not be the case.

In addition, the housing inside walls 603 provide guides for channellingthe air and aerosol flow between the capillary wick and heating coil andthe air outlet. The housing inside walls 603 also define the aerosolforming chamber 602. In this embodiment, the housing inside walls 603are shaped so as to direct the air and aerosol flow substantially in thedirection of the longitudinal axis of the housing.

FIG. 6b shows a second arrangement of the smoking system 600′. Thearrangement shown in FIG. 6b is identical to that shown in FIG. 6aexcept that an additional insert 605 is provided in the smoking system600′ of FIG. 6b . The additional insert 605 provides additional guidesfor directing air flow. The insert 605 is a ribbed insert surroundingthe capillary wick and heating coil. It is shaped so as to direct theair flow onto the capillary wick and heating coil in a substantiallyradial direction, that is to say, substantially perpendicular to thelongitudinal axis of the housing.

FIG. 6c shows a third arrangement of the smoking system 600″. Thearrangement shown in FIG. 6c is identical to that shown in FIG. 6aexcept that an additional insert 607 is provided in the smoking system600″ of FIG. 6c . The additional insert 607 provides additional guidesfor directing air flow. The insert 607 is a grill insert including atube having a number of longitudinally spaced holes. The insert 607surrounds the capillary wick and heating coil and directs the air flowthrough the holes in the grill and onto the capillary wick and heatingcoil in a substantially radial direction, that is to say, substantiallyperpendicular to the longitudinal axis of the housing.

FIG. 6d shows a fourth arrangement of the smoking system 600″′. Thearrangement shown in FIG. 6d is identical to that shown in FIG. 6aexcept that an additional insert 609 is provided in the smoking system600″′ of FIG. 6d . The additional insert 609 provides additional guidesfor directing air flow. The insert 609 is a grooved insert including asolid cylindrical tube having a number of channels formed in the radialdirection. The insert 609 surrounds the capillary wick and heating coiland directs the air flow through the radial channels and onto thecapillary wick and heating coil in a substantially radial direction,that is to say, substantially perpendicular to the longitudinal axis ofthe housing.

FIG. 6e shows a fifth arrangement of the smoking system 600″″. Thearrangement shown in FIG. 6e is identical to that shown in FIG. 6aexcept that an additional insert 611 is provided in the smoking system600″″ of FIG. 6e . The additional insert 611 provides additional guidesfor directing air flow. The insert 611 is a grooved insert including asolid conical tube having a number of channels formed in the radialdirection. The insert 611 surrounds the capillary wick and heating coiland directs the air flow through the radial channels and onto thecapillary wick and heating coil in a substantially radial direction,that is to say, substantially perpendicular to the longitudinal axis ofthe housing.

The embodiments shown in FIG. 6a to 6e provide a substantially radiallydirected air flow onto the capillary wick and heating coil and asubstantially axially directed air and aerosol flow downstream of thecapillary wick and heating coil. It has been found that managing airflow in this way improves the aerosol formation occurring within thesmoking system. The guides provided by the insert 601, and theadditional insert 605, 607, 609, 611 if present, channel the air flow asto direct the air flow onto the capillary wick and heating coil in asubstantially radial direction. This provides the capillary wick andheating coil with cool, non-saturated air, which decreases the particlesize of the aerosol inhaled by a user. The guides provided by thehousing inside walls 603 reduce the volume of the cavity in the smokingsystem and therefore improve aerosol flow towards the air outlet. Thisimproves the smoking experience.

A number of variations are possible in the smoking systems of FIGS. 6ato 6e . First, although the cross section of the device is shown ascircular in FIGS. 6a to 6e , this need not be the case. Second, morethan one air inlet may be provided. The guides upstream of the capillarywick and heating coil may be formed as one or more removable portions(inserts 601, 605, 607, 609 and 611, as shown) or alternatively as anintegral part of the housing or as a combination of both. Similarly, theguides downstream of the capillary wick and heating coil may be formedas one or more removable portions or alternatively as an integral partof the housing (shaped housing inside walls 603, as shown) or as acombination of both. The insert 601 is shown without channels, althoughlongitudinal channels towards the outside of the insert may be provided.In addition, if channels are provided, the insert may extend across theentire cross section of the housing. Any configuration of channels maybe provided. The channels may be twisted around the axis of the housing,so as to encourage a swirled airflow. The channels in inserts 601, 605,609, 611 and the holes in insert 607 may be formed by machining.Alternatively, the insert may be formed with channels or holes alreadyformed, by injection molding. Any number of holes or channels may beformed in inserts 605, 607, 609, 611. Preferably, the insert 601includes a locating pin or protrusion (not shown) on its outer surfacefor cooperating with a recess (also not shown) on the inside of thehousing walls, so as to ensure that the insert is correctly positionedwithin the smoking system. This may be important for the electricalconnections to the heating coil, for example. The inserts 605, 607, 609,611 may also be provided with such a locating pin or protrusion. Thehousing inside walls 603 may be shaped appropriately for the desiredvolume and shape of the aerosol forming chamber within the smokingsystem.

FIGS. 7a to 7c show a sixth embodiment of the smoking system. FIG. 7ashows a cross sectional view of the mouthpiece end of the sixthembodiment of the smoking system 700. In FIG. 7a , the smoking system700 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided by removable insert701 and by the housing walls 703. The air flow is shown by the dottedarrows.

The removable insert 701 is similar to removable insert 601 shown inFIGS. 6a to 6e and extends only across the center of the smoking system700, thereby directing the air flow between the air inlet and thecapillary wick and heating coil to the outer circumference of thedevice. In FIG. 7a , the liquid cartridge, the capillary wick and theheating coil all form part of the removable insert 701, although thisneed not be the case.

In addition, the housing inside walls 703 provide guides for channellingthe aerosol flow onto the capillary wick and heating coil, and betweenthe capillary wick and heating coil and the air outlet. The housinginside walls 703 also define the aerosol forming chamber 702. In thisembodiment, the housing walls 703 are shaped so that the incoming airflow onto the capillary wick and heating coil is directed in an upstreamchannel 705 tangential to the circular cross section of the device andthe circular cross section of the aerosol forming chamber 702.

FIG. 7b is a cross section along line D-D of FIG. 7a . In FIG. 7a thehousing inside walls 703 are shaped so that the channel 705 provides anair flow towards the capillary wick and heating coil that is in thetangential direction. This produces a spiralling air flow around thecapillary wick and heating coil towards the air outlet.

FIG. 7c is a cross section also along line D-D showing an alternativearrangement, in which two channels 705, 705′ towards the capillary wickand heating coil are provided. Both channels direct the air flow in atangential direction and together they produce a spiralling air flowaround the capillary wick and heating coil towards the air outlet.Additional tangential upstream channels could also be provided.

The embodiment shown in FIGS. 7a, 7b and 7c provides a substantiallytangentially directed air flow onto the capillary wick and heating coiland a substantially spiralling air flow around the capillary wick andheating coil and from the capillary wick and heating coil to the airoutlet. It has been found that managing the air flow in this wayimproves the aerosol formation occurring within the smoking system. Theshaped inside walls 703 of the housing, together with the insert 701direct the air flow so as to supply cool and non-saturated air to thecapillary wick and heating coil. Once air flow targets the capillarywick and heating coil, it is immediately evacuated towards the airoutlet. This decreases the particle size of the aerosol inhaled by auser. The spiralling air flow around the capillary wick and heating coilincreases turbulence and reduces aerosol particle size. The size of thetangential channel or channels and its position relative to thelongitudinal axis of the device influence the air flow around thecapillary wick and heating coil and therefore the aerosolcharacteristics. In addition, the centrifugal forces in the spirallingair flow may allow larger aerosol particles to impact and be trapped onthe outer walls of the aerosol forming chamber 702. This is shownschematically in FIG. 7a . The arrangement of FIG. 7c further improvesaerosol formation by providing a better flow distribution within theaerosol forming chamber.

A number of variations are possible in the smoking system of FIGS. 7a,7b and 7c . The cross section of the device is preferably circular, sothat the channel 705 can define a tangential air flow. However, othercross sectional shapes are also possible, as long as some sort ofupstream tangential channel can be defined. More than one air inlet (inthe housing) may be provided. The guides upstream of the capillary wickand heating coil may be formed as one or more removable portions oralternatively as an integral part of the housing or as a combination ofboth (removable insert 701 combined with shaped housing walls 703, asshown). Similarly, the guides downstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing (shaped housing insidewalls 703, as shown) or as a combination of both. The insert 701 isshown without channels, although longitudinal channels towards theoutside of the insert 701 may be provided. In addition, if channels areprovided, the insert may extend across the entire cross section of thehousing. Any configuration of channels may be provided. The channels maybe twisted around the axis of the housing, so as to encourage a swirledairflow. Any channels in insert 701 may be formed by machining.Alternatively, the insert may be formed with channels or holes alreadyformed, by injection molding. The insert 701 may include a locating pinor protrusion (not shown) on its outer surface for cooperating with arecess (also not shown) on the inside of the housing walls, so as toensure that the insert is correctly positioned within the smokingsystem. This may be important for the electrical connections to theheating coil, for example. The housing inside walls 703 may be shapedappropriately for the desired volume and shape of the aerosol formingchamber within the smoking system. This affects the spiralling aerosolflow around the capillary wick and heating coil and therefore theaerosol characteristics. The tangential channels 705, 705′ may bepositioned at any height along the capillary wick and may have anysuitable cross section.

FIGS. 8a to 8c show a seventh embodiment of the smoking system. FIG. 8ashows a cross sectional view of the mouthpiece end of the seventhembodiment of the smoking system 800. In FIG. 8a , the smoking system800 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided by removable insert801, in the shaped housing walls 803 and by impactor 807. The air flowis shown by the dotted arrows.

The removable insert 801 is similar to removable insert 601 shown inFIGS. 6a to 6e and removable insert 701 shown in FIG. 7a and extendsonly across the center of the smoking system 800, thereby directing theair flow between the air inlet and the capillary wick and heating coilto the outer circumference of the device. In FIG. 8a , the liquidcartridge, the capillary wick and the heating coil all form part of theremovable insert 801, although this need not be the case.

In addition, the housing inside walls 803 provide guides for channellingthe air flow onto the capillary wick and heating coil. In thisembodiment, the housing walls 803 are shaped so that the incoming airflow onto the capillary wick and heating coil is directed through anupstream channel 805 tangential to the circular cross section of thedevice and the circular cross section of the aerosol forming chamber802.

In addition, an impactor 807 is provided at the downstream end of thecapillary wick and heating coil. The impactor provides guides forchannelling the air flow away from the capillary wick and heating coiland towards the air outlet. The impactor 807, in conjunction with thehousing inside walls, also defines the aerosol forming chamber 802. Theair flow is directed away from the capillary wick and heating coil inthe radial direction in downstream channels 809, that is to say,substantially perpendicular to the longitudinal axis of the housing. Theimpactor 807 allows larger aerosol particles to be trapped on itsupstream side. This is shown schematically in FIG. 8a . The housinginside walls 803 may be tapered to direct the air flow towards the airoutlet, although this is not shown in FIG. 8 a.

FIG. 8b is a cross section along line E-E of FIG. 8a showing theupstream channel 805. The housing walls 803 are shaped so that thechannel 805 provides an air flow towards the capillary wick and heatingcoil that is in the tangential direction. This produces a spiralling airflow around the capillary wick and heating coil.

FIG. 8c is a cross section along line F-F of FIG. 8a showing thedownstream channels 809. The impactor 807 and housing walls 803cooperate so that the channels 809 provide an air flow away from thecapillary wick and heating coil that is in substantially the radialdirection. That is to say, downstream of the spiralling air flow aroundthe capillary wick and heating coil, the aerosol flow is directed in theradial direction and then towards the air outlet.

The embodiment shown in FIGS. 8a, 8b and 8c provides a substantiallytangentially directed air flow onto the capillary wick and heating coil,a substantially spiralling air flow around the capillary wick andheating coil and a substantially radially directed air flow away fromthe capillary wick and heating coil to the air outlet. It has been foundthat managing the air flow in this way improves the aerosol formationoccurring within the smoking system. The shaped inside walls 803 of thehousing, together with the insert 801 direct the air flow so as tosupply cool and non-saturated air to the capillary wick and heatingcoil. This decreases the particle size of the aerosol inhaled by a user.The spiralling air flow around the capillary wick and heating coilincreases turbulence and reduces aerosol particle size. Larger aerosolparticles may also become trapped on the inside walls of the aerosolforming chamber 802 due to centrifugal forces. This is shownschematically in FIG. 8a . The radially directed outgoing air flow meansthat once air flow targets the capillary wick and heating coil, it isimmediately evacuated towards the air outlet. Additional upstreamtangential channels may be provided (as in FIG. 7c for example) whichmay provide a better flow distribution within the aerosol formingchamber. The size of the tangential channel or channels and its positionrelative to the longitudinal axis of the device influence the air flowaround the capillary wick and heating coil and therefore the aerosolcharacteristics. In addition, the impactor may allow larger aerosolparticles to impact on its upstream wall. This is shown schematically inFIG. 8 a.

A number of variations are possible in the smoking system of FIGS. 8a,8b and 8c . The cross section of the device is preferably circular, sothat the channel 805 can define a tangential air flow. However, othercross sectional shapes are also possible, as long as an upstreamtangential channel can be defined. More than one air inlet (in thehousing) may be provided. The guides upstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing or as a combination ofboth (removable insert 801 combined with shaped housing walls 803, asshown). Similarly, the guides downstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing or as a combination ofboth (shaped housing inside walls 803 combined with impactor 807, asshown). The insert 801 is shown without channels, although longitudinalchannels towards the outside of the insert 801 may be provided.

In addition, if channels are provided, the insert may extend across theentire cross section of the housing. Any configuration of channels maybe provided. The channels may be twisted around the axis of the housing,so as to encourage a swirled airflow. Any channels in insert 801 may beformed by machining. Alternatively, the insert may be formed withchannels or holes already formed, by injection molding. The insert 801may include a locating pin or protrusion (not shown) on its outersurface for cooperating with a recess (also not shown) on the inside ofthe housing walls, so as to ensure that the insert is correctlypositioned within the smoking system. This is important for theelectrical connections to the heating coil, for example. The housinginside walls 803 may be shaped appropriately for the desired volume andshape of the aerosol forming chamber within the smoking system. Thisaffects the spiralling aerosol flow around the capillary wick andheating coil and therefore the aerosol characteristics. The tangentialchannel 805 may be positioned at any height along the capillary wick andmay have any suitable cross section. Any number of radial channels 809may be provided. The impactor 807 may be formed with any appropriateshape and is preferably designed in conjunction with the shaped housinginside walls 803, in order to channel the air flow as desired.

FIGS. 9a to 9d show an eighth embodiment of the smoking system. FIG. 9ashows a cross sectional view of the mouthpiece end of the eighthembodiment of the smoking system 900. In FIG. 9a , the smoking system900 includes guides for channelling the air flow within the smokingsystem. In this embodiment, the guides are provided in removable insert901 and in the shaped housing walls 903. The air flow is shown by thedotted arrows.

The removable insert 901 is similar to removable inserts 601, 701 and801 and extends only across the center of the smoking system 900,thereby directing the air flow between the air inlet and the capillarywick and heating coil to the outer circumference of the housing. In FIG.9a , the liquid cartridge, the capillary wick and the heating coil allform part of the removable insert 901, although this need not be thecase.

In addition, the housing inside walls 903 provide guides for channellingthe aerosol flow onto the capillary wick and heating coil and off thecapillary wick and heating coil. In this embodiment, the housing walls903 are shaped so that the incoming air flow onto the capillary wick andheating coil is directed through an upstream channel 905 tangential tothe circular cross section of the housing and the circular cross sectionof the aerosol forming chamber 902. In addition, the housing walls 903are shaped so that the outgoing air flow off the capillary wick andheating coil is directed through an downstream channel 907 alsotangential to the circular cross section of the housing and the circularcross section of the aerosol forming chamber 902. In addition, thehousing walls 903 are shaped to provide an impactor surface 909downstream of the capillary wick and heating coil. The impactor surface909 may allow larger aerosol particles to be trapped. This is shownschematically in FIG. 9a . The housing inside walls also define theaerosol forming chamber 902. The housing inside walls 903 may be taperedto direct the air flow towards the air outlet, although this is notshown in FIG. 9 a.

FIG. 9b is a cross section along line G-G of FIG. 9a showing theupstream channel 905. The housing walls 903 are shaped so that thechannel 905 provides an air flow towards the capillary wick and heatingcoil that is in the tangential direction. This produces a spiralling airflow around the capillary wick and heating coil.

FIG. 9c is a cross section along line H-H of FIG. 9a showing thedownstream channel 907. The housing walls 903 are shaped so that thechannel 907 provides an air flow away from the capillary wick andheating coil that is in the tangential direction. That is to say, afterthe air has spiralled around the capillary wick and heating coil, it isdirected in the tangential direction and then towards the air outlet.

FIG. 9d shows an alternative cross section along line H-H of FIG. 9a ,also showing downstream channel 907′. In FIG. 9c , the channel 907 is onthe same side of the device as the channel 905. In FIG. 9d , the channel907′ is on the opposite side of the device as the channel 905.

The embodiment shown in FIGS. 9a, 9b, 9c and 9d provides a substantiallytangentially directed air flow onto the capillary wick and heating coil,a substantially spiralling air flow around the capillary wick andheating coil and a substantially tangentially directed air flow off thecapillary wick and heating coil and then to the air outlet. It has beenfound that managing the air flow in this way improves the aerosolformation occurring within the smoking system.

The shaped inside walls 903 of the housing, together with the insert 901direct the air flow so as to supply cool and non-saturated air to thecapillary wick and heating coil. This decreases the particle size of theaerosol inhaled by a user. The spiralling air flow around the capillarywick and heating coil increases turbulence and reduces aerosol particlesize. Larger aerosol particles may also become trapped on the insidewalls of the aerosol forming chamber 902 due to centrifugal forces. Thisis shown schematically in FIG. 9a . The tangentially directed outgoingair flow means that once air flow has circled the capillary wick andheating coil, it is immediately evacuated towards the air outlet.Additional upstream or downstream tangential channels may be providedwhich may provide a better flow distribution within the aerosol formingchamber. The size of the tangential channels and their position relativeto the longitudinal axis of the device influence the air flow around thecapillary wick and heating coil and therefore the aerosolcharacteristics.

A number of variations are possible in the smoking system of FIGS. 9a,9b, 9c and 9d . The cross section of the device is preferably circular,so that the channels 905 and 907 can define a tangential air flow.However, other cross sectional shapes are also possible as long astangential channels can be defined. More than one air inlet (in thehousing) may be provided. The guides upstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing or as a combination ofboth (removable insert 901 combined with shaped housing walls 903, asshown). Similarly, the guides downstream of the capillary wick andheating coil may be formed as one or more removable portions oralternatively as an integral part of the housing (shaped housing walls903, as shown) or as a combination of both.

Moreover, the insert 901 is shown without channels, althoughlongitudinal channels towards the outside of the insert 901 may beprovided. In addition, if channels are provided, the insert may extendacross the entire cross section of the housing. Any configuration ofchannels may be provided. The channels may be twisted around the axis ofthe housing, so as to encourage a swirled airflow. Any channels ininsert 901 may be formed by machining. Alternatively, the insert may beformed with channels or holes already formed, by injection molding. Theinsert 901 may include a locating pin or protrusion (not shown) on itsouter surface for cooperating with a recess (also not shown) on theinside of the housing walls, so as to ensure that the insert iscorrectly positioned within the smoking system. This is important forthe electrical connections to the heating coil, for example. The housinginside walls 903 may be shaped appropriately for the desired volume andshape of the aerosol forming chamber within the smoking system. Thisaffects the spiralling aerosol flow around the capillary wick andheating coil and therefore the aerosol characteristics. The tangentialchannels 905, 907 may be positioned at any height along the capillarywick and may have any suitable cross section. Any number of tangentialupstream and downstream channels may be provided.

FIGS. 10a to 10d show a ninth embodiment of the smoking system. FIG. 10ashows a cross sectional view of the smoking system including removableinsert 1001. FIG. 10b is a cross section along line B-B of FIG. 10a ,showing the mouthpiece end only. FIG. 10c is a cross section along lineC-C of FIG. 10a , showing the mouthpiece end only. In FIGS. 10a, 10b and10c , the smoking system 1000 includes guides for channelling the airflow within the smoking system. The air flow is shown by the dottedarrows.

The removable insert 1001 is shown in cross section in FIG. 10a . Theinsert includes upstream channels 1003 for channelling the air flow fromthe air inlet onto the capillary wick and heating coil and downstreamchannels 1005 for channelling the air flow away from the capillary wickand heating coil towards the air outlet. The channels 1003 and 1005 aresubstantially perpendicular to one another and also substantiallyperpendicular to the longitudinal axis of the housing.

FIG. 10b shows across section along B-B of FIG. 10a and FIG. 10c shows across section along C-C of FIG. 10a . As seen in FIGS. 10b and 10c , inthis embodiment, the guides are provided by removable insert 1001 andremovable insert 1007. The removable insert 1007 is similar to removableinserts 601, 701, 801 and 901 and extends only across the center of thesmoking system 1000, thereby directing the air flow between the airinlet and the capillary wick and heating coil to the outer circumferenceof the housing. In FIGS. 10b and 10c , the liquid cartridge, thecapillary wick and the heating coil all form part of the removableinsert 1007, although this need not be the case. The removable insert1001 is positioned around the capillary wick and heating coil. Theremovable insert 1001 extends across the entire cross section of thedevice.

Because FIG. 10b shows across section along B-B of FIG. 10a , FIG. 10bshows the air flow upstream of the capillary wick and heating coil. Asshown in FIGS. 10a and 10b , the channels 1003 direct the air flow ontothe capillary wick and heating coil in a substantially radial direction,that is to say, substantially perpendicular to the longitudinal axis ofthe housing.

Because FIG. 10c shows across section along C-C of FIG. 10a , FIG. 10cshows the air flow downstream of the capillary wick and heating coil. Asshown in FIGS. 10a and 10c , the channels 1005 direct the air flow awayfrom the capillary wick and heating coil in a substantially radialdirection. In addition, the channels 1005 define the aerosol formingchamber 1002.

The housing walls may additionally be tapered towards the air outlet,although this is not shown in FIGS. 10b and 10 c.

FIG. 10d shows an alternative arrangement for the removable insert1001′. In this embodiment, the insert includes four upstream channels1003′ for channelling the air flow from the air inlet onto the capillarywick and heating coil. As in FIG. 10a , the insert also includes twodownstream channels 1005′ for channelling the air flow away from thecapillary wick and heating coil towards the air outlet. The channels1003′ and 1005′ are substantially perpendicular to the longitudinal axisof the housing. The channels are directed in the radial direction.Although two upstream channels 1003 are shown in FIG. 10a and fourupstream channels 1003′ are shown in FIG. 10d , any suitable number ofupstream channels may be provided, all in the radial direction andsubstantially perpendicular to the longitudinal axis of the housing.Similarly, although two downstream channels 1005, 1005′ are shown inFIGS. 10a and 10d , any suitable number of downstream channels may beprovided, all in the radial direction and substantially perpendicular tothe longitudinal axis of the housing.

The embodiments shown in FIGS. 10a to 10d provide a substantiallyradially directed air flow onto the capillary wick and heating coil anda substantially radially directed air flow off the capillary wick andheating coil. It has been found that managing air flow in this wayimproves the aerosol formation occurring within the smoking system. Theguides provided by the inserts 1007 and 1001 channel the air flow as todirect the air flow onto the capillary wick and heating coil in asubstantially radial direction. This provides the capillary wick andheating coil with cool, non-saturated air, which decreases the particlesize of the aerosol inhaled by a user. The guides provided by the insert1001 channel the air flow as to direct the air flow off the capillarywick and heating coil in a substantially radial direction and alsoreduce the volume of the aerosol forming chamber 1002 in the smokingsystem. This improves aerosol flow towards the air outlet. This improvesthe smoking experience.

A number of variations are possible in the smoking system of FIGS. 10ato 10d . First, although the cross section of the device is shown ascircular in FIGS. 10a to 10d , this need not be the case. Second, morethan one air inlet may be provided. The guides upstream of the capillarywick and heating coil may be formed as one or more removable portions(inserts 1001 and 1007, as shown) or alternatively as an integral partof the housing or as a combination of both. Similarly, the guidesdownstream of the capillary wick and heating coil may be formed as oneor more removable portions (insert 1001, as shown) or alternatively asan integral part of the housing or as a combination of both. The insert1007 is shown without channels, although longitudinal channels towardsthe outside of the insert may be provided.

In addition, if channels are provided, the insert may extend across theentire cross section of the housing. Any configuration of channels maybe provided. The channels may be twisted around the axis of the housing,so as to encourage a swirled airflow. The channels in insert 1007 may beformed by machining. Alternatively, the insert may be formed withchannels or holes already formed, by injection molding. Preferably, theinsert 1007 includes a locating pin or protrusion (not shown) on itsouter surface for cooperating with a recess (also not shown) on theinside of the housing walls, so as to ensure that the insert iscorrectly positioned within the smoking system. This is important forthe electrical connections to the heating coil, for example.

Any suitable configuration of channels may be provided in insert 1001.The channels may be evenly or non-evenly distributed circumferentiallyaround the insert. The channels may have a constant cross sectionalshape and area along their length, or the cross sectional shape can varyalong the length. The channels may include some channels havingdifferent cross sectional shapes and areas from others. The channels ininsert 1001 may be formed by machining. Alternatively, the insert may beformed with channels or holes already formed, by injection molding.Preferably, the insert 1001 includes a locating pin or protrusion (notshown) on its outer surface for cooperating with a recess (also notshown) on the inside of the housing walls, so as to ensure that theinsert is correctly positioned within the smoking system. This isimportant for the electrical connections to the heating coil, forexample. The channels 1005 may be shaped appropriately for the desiredvolume and shape of the aerosol forming chamber within the smokingsystem.

FIGS. 11a to 11n show a tenth embodiment of the smoking system. In eachof FIGS. 11a to 11 n, the smoking system includes guides for channellingthe air flow within the smoking system. The air flow is shown by thedotted arrows.

FIG. 11a shows a first arrangement of the smoking system 1100, and FIG.11b is a cross section along line J-J of FIG. 11a . In FIGS. 11a and 11b, the guides are provided by removable insert 1101, second removableinsert 1103 and by the shaped housing inside walls 1105. The removableinsert 1101 extends only across the center of the smoking system 1100,thereby directing the air flow between the air inlet and the capillarywick and heating coil to the outer circumference of the housing. In FIG.11a , the liquid cartridge, the capillary wick and the heating coil allform part of the removable insert 1101, although this need not be thecase.

Preferably, the second removable insert 1103 is shaped so that the airflow is directed across the capillary wick and heating coil in asubstantially perpendicular direction. That is to say, the air flow issubstantially perpendicular to the longitudinal axis of the housing andto the capillary wick. The second removable insert 1103 provides anupstream channel 1107 on one side of the insert and an downstreamchannel 1109 on the other side of the insert. When the insert ispositioned around the capillary wick and heating coil, the air thereforeflows directly across the capillary wick and heating coil. The insert1103 also defines the aerosol forming chamber 1102.

In addition, the housing inside walls 1005 provide guides forchannelling the air and aerosol flow between the capillary wick andheating coil and the air outlet. In this embodiment, the housing insidewalls 1105 are tapered towards the air outlet so as to direct the airand aerosol flow towards the air outlet.

FIG. 11c shows a second arrangement of the smoking system 1100′ and FIG.11d is a cross section along line K-K of FIG. 11c . The arrangementshown in FIGS. 11c and 11d is identical to that shown in FIGS. 11a and11b except that second removable insert 1103 includes a perturbator 1111surrounding the capillary wick and heating coil. In this embodiment, theperturbator 1111 includes a cylindrical tube surrounding the capillarywick and heating coil, with holes to direct the air flow onto and awayfrom the capillary wick and heating coil. This provides additionalturbulence in the aerosol forming chamber 1102.

FIG. 11e shows another embodiment of removable insert 1103′. Theembodiment shown in FIG. 11e is identical to that shown in FIG. 11bexcept that the aerosol forming chamber is formed with restrictions 1117towards the downstream side. The restrictions 1117 provide turbulenceand, in particular, allow the air flow to strike the downstream side ofthe capillary wick and heating coil.

FIG. 11f shows another embodiment of removable insert 1103″. Theembodiment shown in FIG. 11f provides two upstream channels 1107 a and1107 b on opposite sides of the insert and two downstream channels 1109a and 1109 b on opposite sides of the insert. Air flow is directed fromupstream channel 1107 a, directly across the capillary wick and heatingcoil, towards downstream channel 1109 b. At the same time, air flow isdirected in the opposite direction from upstream channel 1107 b,directly across the capillary wick and heating coil, towards downstreamchannel 1109 a. This provides additional turbulence. In FIG. 11f , theaerosol forming chamber is formed with divisions 1119. This prevents orreduces flow from upstream channel 1107 a to downstream channel 1109 aand from upstream channel 1107 b to downstream channel 1109 b. In FIG.11f , the aerosol forming chamber is formed with restrictions 1117′towards each downstream side, although the restrictions 1117′ may beomitted. The restrictions 1117′ provide turbulence and, in particular,allow the air flow to strike the downstream side of the capillary wickand heating coil.

FIG. 11g shows another arrangement of the smoking system. In FIG. 11g ,only the liquid cartridge, the capillary wick and the heating coil areshown for clarity. FIG. 11h is a cross section, similar to the crosssections in FIGS. 11b, 11d, 11e and 11f , but showing the FIG. 11garrangement. In FIGS. 11g and 11h , two pins 1119, 1121 are provided inthe air flow across the capillary wick and heating coil. The pins directthe air flow and provide further turbulence in the aerosol formingchamber. In the embodiment shown in FIGS. 11g and 11h , the pins are theconnection pins for the heating coil, pin 1119 being the positiveconnection, pin 1121 being the negative connection. However, this neednot be the case.

FIG. 11i shows an alternative version for the arrangement shown in FIG.11g . In FIG. 11i , the pins 1119′, 1121′ are formed as flags. Pin 1119′has a pin portion 1119 a at its base and a wider blade portion 1119 b atits upper part. Similarly, pin 1121′ has a pin portion 1121 a at itsbase and a wider blade portion 1121 b at its upper part. This providesbetter direction of the air flow across the capillary wick and heatingcoil. FIG. 11j shows another alternative version for the arrangementshown in FIG. 11g . In FIG. 11j , the pins are formed as wide heatingblades 1119″, 1121″. Again, this provides better direction of the airflow across the capillary wick and heating coil.

FIGS. 11k and 11l show two alternative arrangements for the pins shownin FIGS. 11i and 11j . FIG. 11k is a cross section, similar to the crosssections in FIGS. 11b, 11d, 11e, 11f and 11h . As shown in FIG. 11k ,the blade portions of the pins may be straight and directed in thedownstream direction, that is to say, towards the downstream channel1109. FIG. 11l is a cross section, similar to the cross sections inFIGS. 11b, 11d, 11e, 11f, 11h and 11k . As shown in FIG. 11l , the bladeportions of the pins may be curved and directed in the downstreamdirection, that is to say, towards the downstream channel 1109.

The embodiments shown in FIGS. 11a to 11l provide a substantiallyradially directed air flow onto the capillary wick and heating coil anda substantially radially directed air flow off the capillary wick andheating coil. In particular, the air flow is directed across thecapillary wick and heating coil. It has been found that managing airflow in this way improves the aerosol formation occurring within thesmoking system. The guides provided by the inserts 1101 and 1103 channelthe air flow as to direct the air flow onto the capillary wick andheating coil in a substantially radial direction. This provides thecapillary wick and heating coil with cool, non-saturated air, whichdecreases the particle size of the aerosol inhaled by a user. The guidesprovided by the insert 1103 channel the air flow as to direct the airflow off the capillary wick and heating coil in a substantially radialdirection and also reduce the volume of the aerosol forming chamber inthe smoking system. This improves aerosol flow towards the air outlet.In addition, in the air flow, additional components may be provided toincrease turbulence. This improves the smoking experience.

A number of variations are possible in the smoking system of FIGS. 11ato 11l . First, although the cross section of the device is shown ascircular in FIGS. 11a to 11l , this need not be the case. Second, morethan one air inlet may be provided. The guides upstream of the capillarywick and heating coil may be formed as one or more removable portions(inserts 1101 and 1103, as shown) or alternatively as an integral partof the housing or as a combination of both. Similarly, the guidesdownstream of the capillary wick and heating coil may be formed as oneor more removable portions or alternatively as an integral part of thehousing or as a combination of both (insert 1103 and shaped housingwalls 1105, as shown). The insert 1101 is shown without channels,although longitudinal channels towards the outside of the insert may beprovided. In addition, if channels are provided, the insert may extendacross the entire cross section of the housing. Any configuration ofchannels may be provided. The channels may be twisted around the axis ofthe housing, so as to encourage a swirled airflow. The channels ininsert 1101 may be formed by machining. Alternatively, the insert may beformed with channels or holes already formed, by injection molding.Preferably, the insert 1101 includes a locating pin or protrusion (notshown) on its outer surface for cooperating with a recess (also notshown) on the inside of the housing walls, so as to ensure that theinsert is correctly positioned within the smoking system. This may beimportant for the electrical connections to the heating coil, forexample.

Any suitable configuration of channels may be provided in insert 1103including any suitable number of upstream channels and any suitablenumber of downstream channels. The channels may have a constant crosssectional shape and area along their length, or the cross sectionalshape can vary along the length. The channels may include some channelshaving different cross sectional shapes and areas from others. Thechannels in insert 1103 may be formed by machining. Alternatively, theinsert may be formed with channels or holes already formed, by injectionmolding. Preferably, the insert 1103 includes a locating pin orprotrusion (not shown) on its outer surface for cooperating with arecess (also not shown) on the inside of the housing walls, so as toensure that the insert is correctly positioned within the smokingsystem. The insert 1103 may be shaped appropriately for the desiredvolume of the aerosol forming chamber within the smoking system.

The pins shown in FIGS. 11g to 11l may have suitable shape in order todirect the air flow across the capillary wick and heating element asdesired. In addition, although the pins are shown as the connections tothe heating coil, this need not be the case.

A large number of embodiments have been described and it should beunderstood that features described in relation to one embodiment mayalso apply to another embodiment, where appropriate. The scope of thepresent invention is defined with reference to the following claims.

In this specification, the word “about” is often used in connection withnumerical values to indicate that mathematical precision of such valuesis not intended. Accordingly, it is intended that where “about” is usedwith a numerical value, a tolerance of ±10% is contemplated for thatnumerical value.

In this specification the words “generally” and “substantially” aresometimes used with respect to terms. When used with geometric terms,the words “generally” and “substantially” are intended to encompass notonly features which meet the strict dcfinitions but also features whichfairly approximate the strict definitions.

While the foregoing describes in detail a preferred smoking system andmethods of making with reference to a specific embodiment thereof, itwill be apparent to one skilled in the art that various changes andmodifications may be made to the smoking system and equivalents methodmay be employed, which do not materially depart from the spirit andscope of the invention. Accordingly, all such changes, modifications,and equivalents that fall within the spirit and scope of the inventionas defined by the appended claims are intended to be encompassedthereby.

1-31. (canceled)
 32. A system comprising: a housing having a mouthpieceend and a body end; a storage portion in the housing, the storageportion configured to contain an aerosol-forming material; a wick incommunication with the storage portion; a heater in the housing, theheater configured to heat a portion of the aerosol-forming material; apower supply electrically connected to the heater; at least one guideconfigured to channel air flow towards the wick; an air outlet at themouthpiece end; an air inlet in fluid communication with the air outlet;and a detection system configured to sense a puff.
 33. The system ofclaim 32, wherein the wick comprises a porous material, a capillarymaterial, or both a porous material and a capillary material.
 34. Thesystem of claim 32, wherein the at least one guide comprises a removableinsert and a portion of an inside wall of the housing.
 35. The system ofclaim 32, wherein the at least one guide comprises a removable insert.36. The system of claim 35, wherein the removable insert includes theliquid storage portion, the wick, and the heater.
 37. The system ofclaim 35, wherein the removable insert includes at least one channelconfigured to channel air flow.
 38. The system of claim 37, wherein theat least one channel is twisted around an axis of the housing.
 39. Thesystem of claim 35, wherein the removable insert includes at least twochannels, the at least two channels having different cross-sectionalshapes.
 40. The system of claim 39, wherein the at least two channelsare evenly distributed circumferentially around the insert.
 41. Thesystem of claim 39, wherein the at least two channels are non-evenlydistributed circumferentially around the insert.
 42. The system of claim35, wherein the removable insert is a grill insert including a pluralityof longitudinally spaced holes.
 43. The system of claim 35, wherein theremovable insert is a grooved insert including a solid cylindrical tubehaving a plurality of channels formed in a radial direction.
 44. Thesystem of claim 35, wherein the removable insert is a grooved insertincluding a solid conical tube having a plurality of channels formed ina radial direction.
 45. The system of claim 35, wherein the removableinsert substantially surrounds the wick and the heating coil.
 46. Thesystem of claim 32, further comprising: an impactor in the housing, theimpactor configured to reduce a particle size of particles.
 47. Thesystem of claim 32, wherein the at least one guide comprises an insidewall of the housing.
 48. The system of claim 47, wherein the inside wallof the housing is tapered towards the air inlet.